Some regions might be supported, but might not be returned in the results of the Get-AWSRegion cmdlet.
An example is the Asia Pacific (Osaka) Region (ap-northeast-3). If you are not able
to specify a region by adding the -Region
parameter, try specifying the region in a custom endpoint instead, as shown in the
next section.

Specifying a Custom or Nonstandard Endpoint

Specify a custom endpoint as a URL by adding the -EndpointUrl common parameter to your AWS Tools for PowerShell command, in the following sample
format.

The following is an example using the Get-EC2Instance cmdlet. The custom endpoint is in the us-west-2, or US West (Oregon) Region in this example, but you can use any other supported
AWS region, including regions that are not enumerated by Get-AWSRegion.